package com.yootk;

import java.util.HashMap;
import java.util.Map;

public class map {
    public static void main(String[] args) throws Exception{
        Map<Integer,String> map = new HashMap<>();
        map.put(1,"edu.yootk.com");
        map.put(2,"www.yootk.com");
        map.put(null,"沐言科技");
        map.put(0,null);
        System.out.println("【KEY存在】查询“key=1”的结果："+map.get(1));
        System.out.println("【KEY存在】查询“key=null”的结果："+map.get(null));
        System.out.println("【KEY存在】查询“key=9 ”的结果："+map.get(9));
    }
}
